Abstract
Oospores of Phytophthora vignae were prepared by repeated floatation and sedimentation of macerated colonies on V-8 Juice agar containing β-sitosterol. Approximately 106 of almost pure oospores were harvested from an agar plated culture in 9cm Petri-dish. Some of the oospores formed in the dark at 25C, germinated even 10 days after they were produced. The percentage of germination increased with their age, being highest from 20 to 90 days after they were produced. Oospores, 30days old, germinated with or without light during their production and germination, though it stimulated the germination and increased the percentage.
